Elevations can be extracted automatically from image acquisition undertaken from a wide range of image sensors; namely, aerial cameras including digital, video, metric and non-metric cameras, calibrated SPOT imagery, IRS 1D, IKONOS and QuickBird. An automated radiometric correlation technique is used by SANI-ITA for processing overlapping pairs of images that provide fast and accurate elevations. The grid size and the extent of the digital elevation model to be collected are interactively specified before the launch of the automated process. Exclusion areas can also be specified during the automated extraction process. The elevations once collected, can be edited using softcopy photogrammetry terrain editing tools. This is accomplished through functions applicable either to individual points, or to groups of points specified by interactively user-defined polygons.

Applications

• 3D visualization by draping on top of the DEM georeferenced imagery, vectors or annotation layers
• orthorectification
• volumetric computation
• cut and fill analysis
• profiles and cross sections
• environmental studies